Improvement in sewing-machine casters



l. ROBERTSUN. Sewing-Machines Gaste'rs.v N0. 141,236, Pa\ tented1uly29,1873.

AM, Mami/mummia co. N Naseem/f mams.;

UNITED STATES PATENT QEEIOEo JAMES ROBERTSON, OF NORTHAMPTON, MASSACHUSETTS, ASSIGNOR TO HIMSELF AND LEANDER W. LANGDON, OF SAME PLAGE.

IMPROVEMENT IN SEWING-MACHINE CASTERS.

Specification forming part of Letters Patent No. llll ,236, dated July 29, 1873 application tiled May 15, 1873.

To all whom it may concern:

Be it known that I, JAMES ROBERTSON, of Northampton, in the county of Hampshire and State of Massachusetts, have invented a new and useful Improvement in Casters for Sewing-Machines; and I do hereby declare the following to be a full, clear, and exact description ofthe same, reference being had to the accompanying drawing making a part of this specification, in which- Figure 1 represents, in perspective, One of the casters complete. Fig. Zrepresents a section through the caster as it appears when the roller is locked so as not to turn, and Fig. 3 represents asimilar section as the several parts appear when the roller is free to run over the door.

My invention consists in a sewing-machine or furniture caster in which the machine or table to which a series Of them is applied shall always rest or stand upon the casterwheels, and which wheels Or rollers are arranged within inverted cups or bowls, against which they are brought and locked by the weight of said machine or table when resting upon them, and unlocked by means of a lever which forces said wheels or rollersfrom contact with said cups or bowls, so as to prevent or admit Of' the moving Of the machine Orl table, as may be desired.

To enable others skilled in the art to make and use my invention, I will proceed to describe the same with reference to the drawings.

A represents the body of one of the casters, thelower portion of which,A', is of a hollowinverted bowl-shaped form, and upon this body is casta seat, B, to hold oneof thelegs of the table or sewing-machine. The wheel or roller G is pivoted to the lugs D in the usual way, and the shank E from which the lugs project passes up through the body of the caster A, and turns freely therein, while the top of the shank may be slightly upset, to prevent it from dropping out of the body, and the top ofthe shank should project a short distance above the top of the body. To the body portion of the caster, as at a, are pivoted the lugs b b Oi' a bent lever, F, the-head c of which lever passes Over and bears upon the head or top Ot' the spindle or shank E 5 and on this lever F there are ears or lugs d d, between which a strap or link may be pivoted, the other end of which is similarly pivoted to a similar lever Or another corresponding caster, so that two or more casters may be operated at one and the same time.

VVheu the lever and its head c is swung O11' to one side of the spindle E, the weight ot' the table Or sewingmachine, coming upon the roller O, forces said roller up into the bowl A' until its perimeter comes in contact with the inner or under surface of the bowl A', as at e, Fig. 2, when the roller becomes locked by contact with said bowl, so that though it still rests upon the loor, and still sustains the Weight of the machine or table, it will not turn. By reversing the operation of the lever the under side oi' its head c bears upon the top of the spindle, forcing it down,and freeing the roller from contact with the bowl, and when thus freed the roller will run, so that, whether the roller be fast or loose, it supports the table or machine, and is in both positions and always in contact with the Hoor.

I have described more particularly a single roller or caster. They are, of course, used in pairs 0r sets.

Having thus fully described my invention, what I claim in a sewing-machine Or furniture caster is The body A A', and the roller or wheel C and its shank E operating therewith, so that by means of the lever F the roller may be allowed, by the weight of the table coming upon it or removed from it, to lock against or be freed from the cup or bowl A', as and for the purpose described and represented.

JAMES ROBERTSON.

Witnesses:

H. K. PARSONS, F. H. RUMMELL. 

